Soil erosion susceptibility assessment in Mediterranean areas by means of soil quality. A test in the Guadalmedina watershed (Málaga,Spain)

Soil erosion is one of the most relevant environmental problems facing society today. Climate change has a direct impact on these processes through a feedback loop, especially in the Mediterranean region, where the situation is conceived as one of extreme fragility. The increase in extreme rainfall and temperature events, together with differential human land use, are leading to an intense degradation of Mediterranean soils. Therefore, it is essential to determine the levels of susceptibility of the landscape to erosion processes to create new strategies to improve the management of the land and reduce the potential risks that may exist. Specifically, this work has focused on the Guadalmedina watershed, in Malaga (Spain), which is characteristic of the current dynamics of the Mediterranean landscape. For this purpose, a soil quality index based on a multi-criteria analysis of different soil indicators (water, physical and organic) has been applied in this study, using a total of 132 soil samples measured in the laboratory. In addition, the results of this analysis have been contrasted with soil erosion values derived from the application of RUSLE model. From this process, those slopes and fields with the highest water erosion risk values have been identified at the most detailed scale. In general, the lowest soil erosion rates are found in those areas where soil quality indicators show optimal values. Furthermore, the results obtained indicate that organic soil indicators are decisive in the processes of water erosion in the Mediterranean area.